Diskectomy in treatment of internal derangement of the temporomandibular joint

Voi. 76 *Vo. 3

September 1991

-

iskectomy in treatment of internal derangement of the temporomandihular joint Follow-up at 1, 3, an Anders B. Holmlund, DDS, PhD,a, Goran Gynther, DDSb and Susanna Axelsson, DDS, PhD,c Huddinge, Sweden KAROLINSKA

INSTITUTE,

HUDDINGE

UNIVERSITY

HOSPITAL

The efficacy of temporomandibular joint diskectomy without implants was evaluated clinically in patients with internal derangements. Seventy-two patients were examined preoperatively and 1 year postoperatively; 40 were also examined 3 years postoperatively and 15 at 5 years after surgery. Success rates were calculated according to a modification of the criteria established in 1984 by the American Association of Oral and Maxillofacial Surgery. The success rate was 83% at the l-year follow-up. Temporomandibular joint pain was alleviated and chewing capacity was normalized in 60 patients. The outcome in 12 patients was classified as unsuccessful, mainly on the basis of residual muscle and joint pain. At the 3-year follow-up only two patients were classified as unsuccessful and none at the 5-year follow-up. Unsuccessfui patients had higher frequencies of muscle soreness and osteoarthrosis than successful patients, Postoperative complications were infrequent and minor. (ORAL SURC ORAL MED ORAL PATHOL 1993;76:266-71)

Diskectomy of the temporomandibular joint (TMJ) was first described by Lanz’ in 1909. Although several studies2-6 have reported high success rates, the method has also been criticized.7-9 It has been claimed that pain relief is more a result of sectioning of sensory nerves that supply the joint than of the diskectomy itself.” The immediate outcome in terms of pain relief may therefore be good, but symptoms eventually recur. It has also been claimed that osteoarthrosis will develop after disk removal.9 The importance of alterations in disk position in the pathogenesis of TMJ internal derangements has been recently questioned.‘O-I2 Internal derangements refractory to nonsurgical treatment frequently exhibit deformation of the disk, and interfering remodelings or osteophytes of the loaded articular cartilage are also implicated.5 As alternatives to open surgery, less invasive surgical procedures such as arthroscopic lysis and lavage and disk repositioning are always attractive. It is, however, also important that the surgical procedure allows optimal inspection of the functional parts of the aAssociate Professor, Department of Oral Surgery. bAssistant Professor, Department of Oral Surgery. CAssistant Professor, Department of Clinical Oral Physiology Copyright @ 1993 by Mosby-Year Book, Inc. 0030-4220/93/$1.00 + .lO 7/12/48523

266

joint and access for effective removal of interfering tissue. Most published studies on TMJ diskectomy are retrospective with inherent weaknesses of high patient drop-out and retrospective analysis of data. A few prospective studies indicate success rates of 80% to 90%.4-6 These studies comprise either rather small materials or short follow-up periods. To obtain more reliable data a prospective study was performed in which a subsample of the patients was followed for up to 5 years. MATERlAL

AND METHODS

During the period 198 5 to 199 1, diskectomies were performed on a total of 110 patients with TMJ internal derangement. At the time of this study 72 patients had been followed for 1 year. The man/woman ratio was 1:7, the left/right joint ratio was I:lS, and the mean age was 37 years (range 19 to 64 years). Unilateral diskectomy was performed in 61 patients and bilateral diskectomy in 11 patients. Forty of these 72 patients were followed for 3 years and 15 patients for 5 years. The drop-out rate (that is, the number of patients not responding to repeated recall letters) was zero at the l-year follow-up, one patient (2%) at the 3-year follow-up and two patients (12%) at the 5-year follow-up.

ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY Volume 76, Number 3

For at least 6 months before surgery all patients were treated nonsurgically with full coverage occlusal stabilization splints and physical therapy. Physical therapy focused on muscle relaxation and posture. Occasionally occlusal equilibration was also performed. Intra-articular injections with corticosteroids were given in seven patients awaiting surgery (one injection of triamcinolone 10 mg/ml; 0.4 ml). The following criteria were used for diskectomy: clinical signs amd symptoms of TMJ internal derangement; pain from the joint that was alleviated by diagnostic local anesthesia of the joint; arthrographic or arthroscopic evidence of TMJ internal derangement. Exclusion criteria were evidence of systemic joint disease and major jaw deformity. The clinical signs and symptoms of internal derangement described by Dolwick13 were used in this study. The arthrographic criterion for internal derangement was evidence of disk deformation on the arthrotomograms. l4 The arthroscopic criteria for internal derangement were pronounced folding of the posterior disk attachment with synovitis and no clear boundary between the posterior band of the disk and the posterior disk attachment.15 Diagnostic local anesthesia was performed according to a previously described standardized technique. l6 Techniques for double-contrast arthrotomography14 and arthroscopy 16,l7 have been earlier described in detail. Clinical examination before surgery and at follow-up was performed according to techniques described by A.gerberg’* and Krogh-Poulsen.19 Arthrography was performed in 35 joints and arthroscopy in 48 joints before surgery. SURGICAL PR:OCEDURE Arthrotomy was performed via a preauricular approach. 2o The lateral capsule was cut horizontally in the superior part, and the upper compartment was then investigated. Dissection was then performed along the lateral part of the condyle to the lateral pole. The lateral disk attachment was cut and the lower compartment explored. A Kirschner wire of 1.1 mm was drilled into the condyle and into the eminence, and the joint slpacewas widened with a retractor. Disk clamps were positioned anterior and posterior to the disk, and complete diskectomy was then performed with a small scalpel. The clamps were then removed, and the temporal and condylar cartilage once more investigated for areas of interfering remodeling. In such case a small arthroplasty was performed with the use of a fine curved bone file. No implants were inserted. No postoperative systemic steroid therapy was given. All patients were given antibiotic coverage for 24 hours p’ostoperatively (cloxacillin 2 gm X 4 IV

Holmlund,

Gynther, and Axelsson

in the majority of patients and clindamycin mg X 3 IV in patients allergic to penicillin).

267 600

POSTOPERATIVE CARE The patients were told to eat a soft diet for the first 2 weeks and then to avoid tough food for at least 2 months. On day 1 after surgery the patient began a training program for maximum opening and protrusive and laterotrusive movements that was supervised by the surgeon. The training was gentle during the first week and then slowly increased. If the prescribed training progra:m caused no improvements or only minor improvement in joint mobility, the patients were referred to the physiotherapist for intensive supervised training. Patients with clenching and grinding habits had t,heir splints adjusted. Occlusion was checked during the follow-up period. No adjustments were made during the first 6 months after surgery. The patients were seen at regular follow-ups at 1 month, 3 months, 6 months, 1 year, 3 years, and 5 years after surgery. POSTOPERATIVE EVALUATION History evaluation The patient was interviewed and specifically asked if there was any pain in the joint area on mandibular movements and if there was any reduction in chewing capacity. Clinical examination Joint and muscle soreness was registered with finger palpation according to established techniques and criteria.18, lg Mandibular vertical and horizontal movements were measured with a ruler. Deviation of the mandible towards the surgically treated side on maximum opening and maximum protrusion was also recorded. Joint sounds were investigated with both finger palpation and auscultation with a stethoscope. Nerve function ‘was tested after surgery with the use of the contralateral joint area as a control. A sharp probe and a small piece of cotton were used to test sensitivity to pain and touch in the area of auriculotemporal innervation. The function of the facial muscles innervated by the superior branches of the facial nerve was; tested. Subcutaneous infection was registered, and if deep infection was suspected, aspiration was performed. The success rate was calculated according to the following criteria, a slight modification of the criteria presented by the American Association of Oral and Maxillofacial Surgeons Ad Hoc Study Group on TMJ Meniscus Surgery. 21The criteria for success were the following: pain that is absent or so mild, brief, and infrequent as to ble of no concern to the patient; range of motion greater than 35 mm for maximum opening

268

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ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY

and Axelsson

September

Table 1. Location of interfering

remodeiings

observed during surgery ! Condyle (n = 20) Temporal (n = 3)

Lateral 8 1

Central 11 1

/

Medial

Table II. Findings before and 1 year after diskectomy on 72 patients with TMJ internal derangement !

1 1

I

and greater than 5 mm for protrusive mandibular movements; regular diet that at worst avoids tough or hard foods; patient must be minimally inconvenienced by diet; and absence of significant complications. For the procedure to be considered unsuccessful, the following must exist: constant or frequent pain; and range of motion less than 36 mm for maximum opening and less than 6 mm for protrusive mandibular movements. Statistical

Findings History Pain on mandibular movements Reduced chewing capacity Clinical Crepitation Clicking Muscle soreness (>2 muscles) Joint soreness Maximum opening <36 mm Maximum protrusion <6 mm

Number of patients (n = 72) I 1 year Before j after surgery surgery

72 61

12 12

9 13 36 68 59 43

54 0 19 12 8 9

methods

Chi-square tests were used to assess if observed frequencies in 2 X 2 contingency tables differed from those expected. The Fisher exact test was used if expected frequencies were less than 5. The statistical analysis was performed on patients with unilateral surgery and the joint exhibiting most symptoms in patients with bilateral diskectomy. ESULTS Diskectomy was performed in 60 joints. In the remaining 23 joints (27%), diskectomy and an additional minor arthroplasty were performed. The locations of the interfering remodelings are shown in Table I. These remodelings were not detected with imaging or arthroscopy in 21 cases (9 1%). Macroscopically all excised disk specimens revealed deviation in form. No complications occurred during surgery or the immediate postoperative period. No deep infection developed after surgery. In one patient slight suppuration was observed around one of the resorbable subcutaneous sutures: the small abscess was incised and the area healed within a few days, Three patients experienced a temporary palsy of the temporal branch of the facial nerve. The nerve branch fully recovered and muscle function was normalized after 3 weeks, 2 months, and 3 months respectively. All patients had some degree of sensory disturbance in the area of auriculotemporal nerve distribution after surgery. At l-year follow-up 15 patients demonstrated small areas of paresthesia in this area. None of these patients reported any discomfort. l-year

1993

follow-up

Table II displays clinical signs and symptoms in 72 patients preoperatively and at l-year follow-up. According to the interview 60 patients (83%) reported no pain on mandibular movements and normalized chew-

ing (p < 0.001). Twelve patients (17%) reported residual pain that varied from slight to moderate and difficulty in chewing tough food and biting an apple. Crepitation was the only clinical sign that was more frequent at l-year follow-up (p < 0.001). Thirteen joints (18%) exhibited clicking before surgery and none at follow-up (p < 0.001). The frequencies of joint (p < 0.001) and muscle soreness (0.001 < p < 0.01) were significantly reduced at follow-up. The mean maximum opening and protrusion of the mandible were increased l-year after surgery (Table III). Slight deviation of the mandible on protrusion or maximum opening was noticed in 31 patients (43%) at l-year follow-up (Table IV). The success rate according to the modified American Association of Oral and Maxillofacial Surgeons criteria was 83% with no difference for patients with diskectomy and diskectomy plus minor arthroplasty (83% in each group). 3-year follow-up

Forty patients were followed for 3 years (Table V). The number of patients with joint pain on mandibular movements and reduction of chewing capacity was lower at this follow-up (p < 0.001). Crepitation was more frequent (p < O.OOl), clicking less frequent (0.001 < p < O.Ol), and joint (p < 0.001) and muscle soreness (0.001

Holmlund,

ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY Volume 76, Number 3 Table 111. Maximum

opening atnd protrusion (mean, range) of mandible before surgery and at l-year follow-up Before surgery Maximum opening (mm) 21.4 mean 10-49 range Protrusion(mm) mean 5.3 O-10 range

opening and protrusion at l-, 3-, and 5-year fOllUW-up

1 year (n = 72) 3 years (n = 4.0) 5 years (n = 15)

diskectomy on 40 patients with TMJ internal derangement Number of patients (n = 40)

31.5 30-5.5 7.0 O-10

Number with deviation 31 (43%) 17 (43%) 8 (20%)

5-year follow-up

Table VII shows clinical signs and symptoms before surgery and at 5-year follow-up. Joint pain on mandibular movements was less frequent and normal chewing capacity more frequent in the 5-year follow-up patients according to the interview (p < 0.001). Crepitation was more frequent at this follow-up (p = 0.02). Clicking was found in two patients before surgery and in no patients at 5-year follow-up (NS). Muscle soreness was less frequent in patients at 5-year follow-up (NS). Joint soreness was not revealed in any of the follow-up patients and contrast’ed to all 15 patients preoperatively (p < 0.001). Mean maximum opening and protrusion were increased in foll’ow-up patients (Table VIII). Slight deviation of the mandible toward the surgically treated side during maximum opening and protrusion was noticed in three patients (20%) (Table IV). According to the success criteria, no patient was regarded as unsuccessful at the 5-year follow-up.

269

Table V. Findings before and 3 years after

I year after surgery

Table IV. Devi,ation of mandible on maximum

Follow-up

Gynther, and Axelsson

Findings

~

History Pain on mandibular movements Reduced chewing capacity Clinical Crepitation Clicking Muscle soreness (>2 muscles) Jloint soreness Maximum opening <36 mm Maximum protrusion <6 mm

zz

~

:Ei

40 36

2 2

8 9 23 39 36 29

28 0 7 2 2 2

Table VI. Maximum opening and protrusion (mean, range) of mandible before surgery and at 3-year follow-up 7

Before surgery Maximum opening (mm) mean 27.8 10-49 range Protrusion(mm) mean 5.5 range l-8

3 years after surgery

39.3 30-55 7.6 5-12

q

Unsuccessful

cases

Twelve pati.ents were regarded as unsuccessful at l-year follow-up. Table IX shows a comparison of successful and unsuccessful groups. Seven patients underwent a second surgical procedure and two patients underwent a third. Two of the treated patients developed a temporary palsy of the temporal branch of the facial nerve. Only one of the treated patients improved. At surgery, slight-to-moderate fibrosis in the lateral part of the joint was found in all cases. Biopsies showed minor inflammation or none at

all. The articulating fibrocartilage appeared somewhat flattened but smooth. In one joint, interfering residual disk tissue was discovered in the medial part. In another joint., hyperplasia of the posterior disk attachment seemed to have developed, leading to an anterior condyle position and alterations in occlusion. Two patients had symptoms at the 3-year followup; both these patients had preoperative muscle soreness and revealed osteoarthrosis during surgery. DISCUSSION

During recent decades the attitude towards TMJ surgery in Sweden has been cautious, and fewer than 1% of patients with TMJ disorders have been surgically treated. 4,g This restrictive approach relates to difficulties in establishing specific criteria for TMJ internal derangements and consequently inappropriate selection of patients for surgery. New diagnostic methods such as arthrography,14 magnetic resonance,22 and arthroscopy16 have improved diagnostic accuracy. As the pathogenesis of TMJ internal derangement is still unclear,” nonsurgical treatment should always be given initially but discontinued if there are no signs of improvement. Delay may lead to

270

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ORAL SURGERY ORAL MEDKINE ORAL PATHOLOGY

and Axelsson

September

Table VII. Findings before and 5 years after diskectomy on 15 patients with TMJ internal derangement

Frequencies of criteria in patients at 1-year follow-up

Table IX.

Number of patients (n = 15)

f Before Findings

surgery

History Pain on mandibular movements Reduced chewing capacity Clinical Crepitation Clicking Muscle soreness (>2 muscles) Joint soreness Maximum opening <36 mm Maximum protrusion <6 mm

5 years after surgery

15 14

0 0

6 2 I 15 13 10

13 0 3 0 0 0

Table VIII. Maximum opening and protrusion (mean, range) of mandible before and 5 years after surgery Before surgery Maximum opening (mm) 21.1 mean lo-42 range Protrusion(mm) mean 5.8 range 3-9

1993

5 years after surgery

42.5 36-55 7.5 6-12

muscle soreness that can affect the outcome of surgery. A major disadvantage in long-term follow-up studies, particularly retrospective studies is patient drop-out. In this prospective study it was possible to minimize drop-out even at the 5-year follow-up, and the calculated success rates in this study should therefore be reliable. Macroscopically, all excised disks revealed some degree of deviation in form. In a previous histologic study on 47 TMJ diskectomies, degenerative changes were found in 53% of the excised disks.23 In such joints, disk repositioning techniques may therefore lack the biologic basis for adaptation and repair. Recent studies of disk repositioning performed both by arthroscopy and open surgery also indicate that in most cases displaced disks are refractive to repositioning attempts. lo, l2 Furthermore, in our study, interfering remodelings were found in more than one fourth of the surgically treated joints. In the vast majority of cases (!?l%), these remodelings (predominantly on the condyle) were not detected in tomograms, arthrograms, or during arthroscopy.

Successful j Unsuccessfui (n=60) j (n=12} Male/female ratio Left/right joint ratio Mean age (range) Muscle soreness (>2 muscles) Hard tissue changes on tomograms Surgery-revealed osteoarthrosis

I:5

1~1.6 1:1.3 36 (19-64) 24 (40%)

I:3 45 (33-62)

16 (27%) 16 (27%)

6 (50%) 6 (50%)

10 (83%)

On the other hand both arthroscopic lysis and lavage’O and disk repositioning surgery12 have been reported to alleviate pain and improve mandibular function. Other mechanisms for TMJ locking such as muscle hyperactivity and the development of a vacuum phenomenon” may therefore also be of importance. With the use of the same inclusion criteria, the success rate for arthroscopic surgery is clearly lower than for diskectomy in our patients. This does not imply that arthroscopic surgery should be avoided. Arthroscopy provides unique possibilities for simultaneous diagnosis and therapy. It is less invasive than open surgery and even if the success rate is lower than for diskectomy a considerable number of patients have been improved and more invasive surgery avoided. There is, however, a need for future randomized trials comparing the different methods. Grepitation was frequently found in operated joints at follow-up, and it has been suggested that diskectomy will result in osteoarthrosis.9 On the basis of prospective imaging data, Eriksson and Westesson6 suggested that the observed remodelings represent functional adaptation of the joint. These remodelings furthermore did not correlate with pain and impaired mandibular function In all patients with disturbing clicking, the clicking disappeared after surgery and did not recur. Deviation of the mandible to the surgically treated side occurred in about 40% of the patients postoperatively. It was minor in the majority of these patients but is an indication of reduced joint translation. No patient, however, reported any related discomfort. When comparing the frequencies of deviation at the 3-year and 5-year follow-ups, it seemed that deviation gradually diminished. Disk-substituting alloplastic implants2” have been used to reduce the risk of postoperative adhesions and to protect the articular cartilage. Results obtained in recent studie& 25,26 have indicated an unfavorable long-term outcome. The use of autogenous materials, such as dermis, temporalis fascia, temporalis muscle, and auricular cartilage have been advocated as alternative implants. Although some promising results have been reported, 27-29there is a lack of long-term

Holmlund,

ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY Volume 76, Number 3

follow-up studies. Randomized trials that compare diskectomy without implants with those that use various alloplastic or autogenousimplants should provide more reliable information. The rather low complication rate in our study is in agreement with recent studies.4,5 The severity of complications was even less than reported for arthroscopic surger:y.30 The number of patients regarded as unsuccessful was relatively small and therefore difficult to analyze. Maximum opening and protrusion of the mandible were improved even in this group, and the patients were mainly classified as unsuccessful becauseof residual joint and muscle pain In the seven treated joints, surgical findings did not explain the residual symptoms in five of them. The poor outcome of a second surgery and the increased risk of facial nerve sequelae indicate a restrictive approach. Osteoarthrosis at surgery and preoperative muscle soreness were more frequent in the unsuccessful group than in the successful group (Table IX). This may indicate that in patients with TMJ internal derangements, nonsurgical treatment without result should not be prolonged. The mean age was 9 years higher in the unsuccessful group and may also indicate a factor of importance. In this study diskectomy without implants seemed efficient also in the long term. Only two patients demonstrated symptoms at the 3-year follow-up and none at the 5-year follow-up. The successrates correlate well with those obtained in recent comparable studies.576 In. conclusion diskectomy without disk-substituting implants seemsto be an effective surgical procedure for alleviation of symptoms and improvement of mandibular function in patients with TMJ internal derangements. It may well serve as a reference procedure in future comparative randomized trials. REFERENCES 1. Lanz A. Dis,citis mandibularis.

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91. 2. Brown WA. Internal derangement of the temporomandibular joint: review of 214 patients following meniscectomy. Can J Surg 1980;23:30-2. 3. Silver CM. Long-term results of meniscectomy of the temporomandibular joint: J Craniomand Pratt 1984;3:46-57. 4. Eriksson L, Westesson P-L. Diskectomy in the treatment of anterior disk displacement of the temporomandibular joint: a clinical and radiographic one-year follow-up study. J Prosthet Dent 1986;55:106-16. 5. Holmlund A, Axelsson S. Diskectomy in treatment of disk derangement: a one- and three-year follow-up. Swed Dent J 1990;14:213.-8. 6. Eriksson L, Westesson P-L. Temporomandibular joint diskectomy: no positive effect of temporary silicone implant in a 5-year follow-up. ORAL SURG ORAL MED ORAL PATHOL 1992;74:259.-72.

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26. Valentine D Jr, Reiman BEF, Beuttenmuller EA, Donovan MG. Light and electron microscopic evaluation of Proplast II TMJ disk implants. J Oral Maxillofac Surg 1989;47:689-96. 21. Ioannides C, Freihofer P. Replacement of the damaged interarticular disk of the TMJ. J Craniomaxillofac Surg 1988; 16:273-g. 28. Meyer RA. The autogenous dermal graft in temporomandibular joint disk surgery. J Oral Maxillofac Surg 1988;46:94854. 29. Feinberg SE, Larson PE. The use of pedicled temporalis muscle-pericranial flap for replacement of the TMJ disk. J Oral Maxillofac Surg 1989;47:142-6. 30. McCain JP, Sanders B, Koslin MG, Quinn JD, Peters PB, Indresano TA. Temporomandibular joint arthroscopy: a 6-year multicenter retrospective study of 4,831 joints. J Oral Maxillofac Surg 1992;50:926-30. Reprint

requests:

Anders B. Holmlund, DDS, PhD Department of Oral Surgery Karolinsha Institute, Box 4064 S-141 04, Huddinge, Sweden